Field
The described technology generally relates to a battery pack.
Description of the Related Technology
In general, unlike primary batteries, secondary batteries are rechargeable. Thus, secondary batteries are applied to various fields such as digital cameras, cellular phones, notebook computers, and hybrid vehicles, and studies on secondary batteries are actively conducted. Examples of secondary batteries include nickel-cadmium batteries, nickel-metal hybrid batteries, nickel-hydrogen batteries, lithium secondary batteries, and the like.
Lithium secondary batteries are frequently used as the power source of electric or hybrid electric vehicles. Such power sources are required to supply high power during activities such as driving a motor. Accordingly, a high-capacity battery pack including a plurality of high-power battery cells or battery modules connected together is typically used as a power source for these high power applications.
As described above, the battery pack ordinarily includes a plurality of battery cells connected in series. Particularly, battery packs used for hybrid electric vehicles, can include up to a few tens of battery cells which are alternately charged and discharged. Such charging and discharging of the battery cells should be controlled. Accordingly, each of the battery cells should be managed to maintain an appropriate operating state.